ITMI950833U1 - CUTTING DEVICE FOR TRIMMING PRINTED PAPER PACKS IN A PACKAGING MACHINE - Google Patents

Abstract

A cutting device for trimming printed paper packages in a packaging machine comprising a cutting unit consisting of an upper part (15) and a lower part (16), at least one of the two parts (15, 16) being movable upwards and downwards on passage of a continuous papery material (12) originating from a reel and of flat tubular form bonded transversely and possibly longitudinally by glue and provided with printed portions (10) separated by a neutral strip (29). One (15) of the two parts (15, 16) of the cutting unit carries two blades (25) spaced apart by a distance similar to the width of the strip, which interact with two counter-blades (45) arranged on the other part (16), elastic presser elements (36) being positioned on at least one (15) of the parts of the cutting unit to act to lock the papery material (12) during the cutting action on the strip, removable elements (27) being provided to vary the distance between the blades and counter-blades (45) as the width of the strip (29) varies. <IMAGE>

Description

DESCRIPTION of the industrial utility model

The present invention relates to a cutting device for trimming packages of printed paper in a packaging machine.

In the industry of packaging of editorial products, communications of promotions for the sale of products or in any case in general in the packaging industry within a wrapping of paper closed along all its sides, reels in printed paper are used with rotary systems that reproduce, one after the other, a plurality of prints which must then be arranged on a single final envelope.

In the processing of these reels with rotary systems it is practically impossible to print the plurality of prints of a single envelope without leaving neutral-colored gaps between a printed area or image and the next. And these gaps are generated from the seaming area to the printing cylinder of the plate on which the image of the single wrapping or single package is reproduced. In this regard, it should be noted that these transversal interspaces to the paper reel vary, for example from 10 to 30 mm, are due precisely to the fixing system of the aforementioned plate and cannot in any way be minimized.

When the printed reel is unwound inside the packaging machine and its lateral edges are wound to overlap and to form a flattened tubular package, these interspaces remain as strips for interrupting the printing between a portion that will form one package and the next. After the bonding phase of the overlapping longitudinal edges of the continuous tubular package with glue or similar product and the introduction of drops or areas of glue also in the vicinity of these transversal interruption strips towards the printed part, the single packages are identified complete and closed along all their sides by cutting in correspondence with the neutral strips mentioned above.

Currently, therefore, between one package and another, or at the two ends of each package once finished and separated, an unsightly strip or part of a strip of neutral color, not printed, is identified, due to the above-mentioned presence of the seaming area in printing stage. And this neutral zone exists at the end and at the beginning of the printed zones of the single package.

The object of the present invention is to provide a device in a packaging machine which eliminates these neutral partial strips or areas in the finished packages.

Another object is to achieve the elimination of such strips even when their size varies on the printed paper reel.

These objects according to the present invention are achieved by realizing a device as the object of claim 1 and of the attached dependent claims.

The characteristics and advantages of a cutting device for trimming packages of printed paper in a packaging machine according to the present invention will become more evident from the following, exemplary and non-limiting description, referring to the attached schematic drawings in which:

Figure 1 is a perspective view of a cutting device for trimming packages of printed paper applicable to a packaging machine for products in paper or the like made according to the present invention, shown in a part thereof being the missing part perfectly symmetrical, and

Figure 2 is an at least partial and enlarged elevation section of the device of Figure 1 in the open position.

With reference to the figures, a cutting device for trimming packages of printed paper according to the present invention is shown in Figure 1 and is indicated as a whole with 11.

A reel of paper or similar paper material is fed into a packaging machine (not shown). As previously said, this paper is turned over on itself, in a known way, and must be constrained both along longitudinal overlapping edges by means of a longitudinal sealing unit (not shown) and in correspondence with transversal head and tail areas of the package so as to identify it. closed and ready for use. In Figures 1 and 2 this continuous paper material is already shown in its folded tubular form flattened in 12, equipped with printed portions 10, before cutting and with 13 in Figure 1 a final end of a finished package 14 is identified.

The application of the neck both at the longitudinal and transverse edges has already occurred in a known way and both the continuous paper material 12 and the finished packages 14 are made to advance by means of conveyors 17 and 18 placed upstream and downstream of the device of the invention 11 , as shown in figure 2.

The device of the invention 11 essentially comprises an upper part, indicated as a whole with 15, in figure 2, and a lower part indicated with 16. It should be noted that this device is placed in a packaging machine in place of and in the position of a traditional cutting unit. and / or transverse welding.

The upper part 15 of the device consists of a cutting unit composed of a support structure 19a and 19b, for example made of high-strength aluminum in three parts and assembled by means of screws. This support structure in the two portions 19b provides for a series of through holes 20b suitable for receiving screws 21 for fastening within threaded holes 20a of a central portion 19a placed between the two side portions 19b. In turn, the side portions 19b are constrained (by means of elements not shown) to a mobile support 22 of the packaging machine which can be moved vertically in raising and lowering. It should be noted how advantageously this mobile support 22 is the one that usually constitutes the support of a common cutting and sealing device of traditional packaging machines. A further series of through holes 23b obtained in the lateral portions 19b of the support structure allows the positioning and locking by means of screws 24 of cutting blades 25, placed on relative attachments or supports 26, also provided with holes 23.

The positioning of the attachments 26 with respect to the side portions 19b can be adjusted and differentiated by means of the arrangement of freely removable elements, such as calibrated shims 27, for example washers, which can be inserted in an interposed position at the time of positioning the screws 24 to constrain the parts. It is therefore possible to vary a width L of the cut.

At least one of the lateral portions 19b of the support structure of the upper part 15 are connected ducts 28 for compressed air designed to send the air inside the cutting unit, or inside the cutting blades 25. The compressed air introduced is used to eject a strip 29, that is to say a so-called trimming, which is identified at the time of making the final package. This neutral strip 29 constitutes an interspace between the printed portions 10 of the tubular continuous paper material 12.

The compressed air supply is activated by a solenoid valve schematized at 30 controlled by a microswitch with relative actuation cam, both indicated with 31, which allows the emission of a breath of air for a few moments and only when the strip 29 is cut. completed. This strip 29 falls and is sucked into an underlying tray 32, equipped with a suction channel, partially shown at 33, suitable for collecting the trimmed waste elements 29. This tray can be placed integrally with the structure of the packaging machine underneath the part bottom 16 of the device.

The couplings or supports 26 are equipped with internal channels connected to ducts 34 for the passage of grease or similar lubricating material for the guides of the cutting blades 25. The lubricating material is pumped in small quantities from a tank (not shown) to which they are the conduits 34 are connected according to the selected times and quantities.

Furthermore, rubberized strips 35 are placed on the lower end surfaces of the attachments or supports 2 6, adapted to cushion the contact with leaf spring pressure elements 36 described hereinafter.

In fact, at extensions 37, placed at opposite ends of the mobile support 22 (only one of which is shown), the leaf spring pressure elements 36 are suspended and constrained. These pressure elements 36, having the function of blocking the continuous paper material 12 during the step of cutting and removing the strip or trim 29, also act to press points or areas of glue previously placed transversely inside the flattened tubular material 12 to identify transverse seals of the finished package 14.

The pressure elements 36 are constrained, as will be seen below, in a displaceable manner with respect to the extensions 37 by means of springs 38. These pressure elements 36 descend simultaneously to the upper part 15 of the device, or of the cutting unit, and first intercept the tubular material flattened 12 locking it by means of rubber strips 39 constrained to their lower surfaces. These rubber strips 39 act as elements that prevent the paper material 12 from slipping during the step of cutting and removing the strip or trimming 29.

As highlighted in fig. 1, for their support and assembly, the pressure elements 36 are connected at their ends by crosspieces 40 to which the springs 38 are connected, in turn connected to the extensions 37 of the mobile support 22. The pressure elements 36, in number of two and placed on opposite sides to the two blades 25, have ends 41 adapted to be housed in seats 42 of the crosspieces 40. Calibrated shims 43 can be inserted into said seats 42, which can be added or removed in equal measure on both sides of the crosspieces 40 in a way to maintain perfect parallelism and coupling with the upper part 15 of the device on which the pressure elements 36 which collaborate with the cutting unit are mounted.

The lower part 16 of the device essentially comprises a lower cutting unit cooperating with the upper cutting unit as well as counterpressor elements.

In fact, a lower support structure 44 is provided, for example made of aluminum, on which cutting counter-blades 45, for example of hardened steel, are mounted, such as the above-mentioned upper cutting blades 25. These blades 45 are also spaced apart so as to be placed at a cutting distance L like the blades 25.

In fact, two central bars 46 are constrained to the lower support 44, placed at opposite ends (only one shown in the drawing), to which the cutting counter-blades 45 are made integral by means of screws 47 passing through holes (not shown) of the cutting counter-blades 45 and lockable to the two central bars 46. Between the two central bars 46 and the cutting counter-blades 45 can be interposed calibrated shims 27 identical to those indicated previously with 27 in the upper cutting unit.

A. a further plate 48, which can be placed integral with the lower support 44 outside the cutting counter-blades 45, is used as an adjustment element. In fact, by means of grains or similar elements 49, which can be screwed into this further plate 48, it is possible to act on the cutting counter-blades 45 to micrometrically adjust their position in order to determine a correct rubbing between the upper blades 25 and the lower counter-blades 45 of the entire group of cut.

It should be noted that between the two counter blades 45 and within a slot 50 obtained in the lower support 44, a passage is identified for the fall of the strips or trimmings 29 which in this way can reach the tray 32 below. Furthermore, it should be noted that a part of the upper smooth surface 51 of the counter blades 45 acts as a counterpressor element, on which the upper pressure elements 36, or rather the rubber strips 39, act and abut to hold the paper material 12.

The operation should be clear from the description above, but it can be briefly mentioned. The packaging machine equipped with the device according to the present invention is arranged as shown in the example to remove neutral strips 29 of the size shown. In this way, upon the advancement of the paper material 12 and its adaptation to the desired tubular shape, packages will be created, also containing further editorial elements or of a different type. These packages are created thanks to the presence and distribution of glue in known previous phases.

It is now necessary to separate the individual packages by eliminating the neutral strip 29, or in any case the part thereof that is to be eliminated, in order to make the finished package. To do this, the device of the present invention is used.

Through a very accurate printing pitch registration system, for example with suitable cells and sensors of the print arranged in the machine, which determines a correct unwinding of the paper in pitch, and actuators (not shown) synchronized to the correct unwinding and determining the lifting and the lowering of the upper part 15 of the cutting unit, the cutting interaction is determined on the continuous paper material 12 in the zone of the neutral strip 29.

The descent of the mobile support 22, of the pressing elements 36 which block the paper material 12 on the smooth part 51 of the upper surface of the counter blade 45, on the opposite sides of the neutral strip 29, and immediately afterwards of the blades 25 interact, is thus promoted. with counter blades 45 and cut the neutral strip 29.

The emission of air is then activated by means of the cam microswitch 31 and the solenoid valve 30 and this air blown between the blades 25 causes the separate strip 29 to fall into the underlying tray 32 which is suctioned through the suction channel 33. The package 14 is therefore ready and trimmed properly according to the cutting width L desired by the user.

If, once this packaging operation has been completed, a reel of paper material 12 has to be treated which has neutral strips 29 between one printed portion and the other of a different size and for example larger than the previous one, the cutting width L must be varied. and simply act as follows.

By acting on the screws 24, some calibrated shims 27 are removed from the upper part 15 of the sealing unit, widening the distance between the blades 25 as necessary. These same calibrated shims 27 removed from the upper part 15 are inserted on the lower part 16 on the screws 47, removed, thus the distance between the counter blades 45 must be widened equally. In order to have a complete adaptation of the entire device it may be necessary to insert calibrated shims 43 in equal measure between the upper pressure elements 36 and their seats 42.

The device was then adapted extremely simply and quickly to the new dimension of the neutral strip 29, generally corresponding to the trimming to be carried out. In the opposite direction, it is possible to act in case the strip is smaller than the one previously treated.

And all this with a single device / with the same blades and counter blades, with the same supports, without any replacement of parts, reducing downtime to zero for adaptation and replacement of operational interacting parts.

With a device according to the present invention it is thus possible to act on neutral strips or trims from about 12 to 27 mm, with the same device and by simply moving the thicknesses. This allows the use of existing printing cylinders with a diameter and lateral surface not perfectly correlated with the length of the printed part of the desired finished package. A less expensive and quicker to use type of offset printing is then used.

Furthermore, the presence of the further plate 49 allows to micrometrically adjust the correctness of the interaction between the blades and the cutting counter-blades at any time.

The suction below allows the strips or trimmings 29 to be evacuated without cluttering the packaging machine.

Even the blade and the counter-blade, for a trim of minimum dimensions, can be made as a pair of side-by-side blades which are sides of a single closed-perimeter die-cut blade, interacting with a counter-blade of the same shape. In this case it is not necessary to adjust the reciprocal position between the parallel blades because they are placed at a fixed distance. It is therefore possible to act on a continuous material printed with a strip or trim of a fixed size.

Claims (14)

CLAIMS 1. Cutting device for trimming packages of printed paper (12) in a packaging machine comprising a cutting unit consisting of an upper part (15) and a lower part (16), in which at least one of the two parts (15, 16) can be moved in lifting and lowering with respect to the other, where between said two parts (15, 16) a continuous paper material (12) coming from a reel, turned up in a tubular form and flattened, longitudinally welded by glue and equipped with transversal gluing areas at the ends of molded portions (10), in which a neutral strip (29) is provided between successive molded portions (10), characterized in that one (15) of said two parts (15, 16) of said cutting unit is composed of a structure (19a, 19b; 26) bearing two blades (25), spaced apart of a size similar to that of said neutral strip or trim (29), which interact with respective two counter blades (45) complementarmen elements arranged on the other (16) of said two parts, elastic pressure elements (36) being arranged on at least one (15) of said two parts of the cutting unit to act to block said paper material (12) during the action of cutting of said neutral strip (29), being further provided freely removable elements (27) adapted to vary a mutual distance between said two blades (25) and two counter-blades (45) as the size of said neutral strip (29) varies. 2. Device according to claim 1, characterized in that said movable part of said cutting unit (15, 16) is said upper part (15). 3. Device according to claim 1 or 2, characterized in that further freely removable elements (43) are also provided, suitable for varying a mutual distance between said elastic pressure elements (36). 4. Device according to claim 1, characterized in that underneath said lower part (16) of said cutting unit there are suction elements (32, 33) of said neutral strips (29) once cut. 5. Device according to claim 4, characterized in that said suction elements are a tray (32) connected to a suction channel (33). 6. Device according to claim 1, characterized in that said pressure elements (36) have rubber strips (39) constrained to their lower surfaces which prevent the slipping of said paper material (12) during the cutting and removal of called strip or trim (29). 7. Device according to claim 1, characterized in that said cutting blades (25) are placed on relative attachments or supports (26), both being (25, 26) provided with holes (23) for positioning with respect to lateral portions (19b) of said structure (19a, 19b) with the interposition of said freely removable elements {21). 8. Device according to claim 1 or 7, characterized in that said freely removable elements for said blades (25) and counter-blades (45) are calibrated shims (27). 9. Device according to claim 8, characterized in that said calibrated shims are washers (27), which can be inserted in an interposed position when positioning screws (24) to constrain said blades (25), said attachments (26) and said portions sides (19b) of said structure to a support (22) of a packaging machine. 10. Device according to claim 1, characterized in that elements for micrometric adjustment (48, 49) of the position with respect to said blades (25) are associated with said counter-blades (45). 11. Device according to claim 10, characterized in that said micrometric adjustment elements comprise a plate (48), which can be placed integral with a support (44) of said counter blades (45) equipped with grains or similar elements (49), which can be screwed into said plate (48) and interacting on said counter-blades (45) to adjust them micrometrically and determine a correct action with said blades (25). 12. Device according to claim 1, characterized in that ducts (28) are connected to an interspace between said blades (25) for sending air capable of expelling said strip (29), once cut from said continuous paper material tubular (12). 13. Device according to claim 1, characterized in that said pressure elements (36) are constrained by interposition of springs (38) to a support (22) for said structure (19a, 19b; 26) bearing said blades (25) . 14. Cutting device for trimming packages of printed paper (12) in a packaging machine as described above as illustrated in the accompanying drawings.